21 Sep
2017
21 Sep
'17
3:52 a.m.
On 09/20/2017 06:55 PM, Dave Horsfall wrote:
Dunno, as I've never used it, but there are some
clever tricks that can
be used to enforce RFC-compliancy (a lot of spamware is written by
idiots who don't understand the finer points of SMTP):
Some of the ones that I've seen make me understand SMTP at all, or if
they are using a library to abstract it.
Enforce proper DNS configuration e.g. must
resolve etc, and must
actually exist.
Make 'em wait a few seconds before sending your own banner, and drop
the connection if they send beforehand.
I do both of those.
Set up an enormous greeting banner (many long
lines); there is nothing
in the RFC that says it has to be a single short line.
I've never thought about a long, multi-line banner.
These simple measures alone cut out most of the crap;
the rest are
handled by various DNSBLs and my private access list.
I agree with the first two, and I'd like to know more about the
effectiveness of the third.
--
Grant. . . .
unix || die